Underfeed stoker



Jan. 22, 1935. H. E PRESTON 1,988,510

UNDERFEED STOKER Filed Oct. 3, 1933 2 Sheets-Sheet l 7N/verzier- Aiiarrzey Herber E. Preson Jam 22, 1935 H. E. PRESTON 1,988,510

UNDERFEED STOKER Filed Oct. 5, 1935 2 Sheets-Sheet 2 .722 Denim ffef'er E. Pres Zon Patented Jan. 22, `1935 Y 1,988,510 n UNDERFEED s'roKER.'

Herbert E. Preston, yPhiladelphia, Pa., assigner American Engineering Company, Philadelphia,

. Pa.,acorporation.ofPennsylvania y v KAppiivmioii october 3, isssgseriarnaeslnsz e claims. (01.;110-244) This invention relates to furnace stokers, and more particularly to stokers'of the multiple retort underfeed type.

Oneobje'ctof thepresent invention is to provide adjustable means adjacent tothe main fuel feeding -mechanismfof a Stoker wherebythe-'depth of the fuel bed and thev density of the fuel 'may be varied to `best suit the operation conditions of the furnace.- Y

A more specific object is to provide in a stoker of the statedV character, a ram box extension plate which is adapted to be'moved'to and held in different positions of adjustment, whereby the density and depth of the fuel bed may be varied and thus insure the best efficiencies under 'all conditions of operation. l

A further object is to provideV a ram box cap extension plate which is simple in construction, and whichY may be readilyrenewed ywithout disturbing other elements of the stoker. A

Other and further objects will become apparent as the description of the invention progresses.`

Of the drawings:

Fig. 1 is a fragmentary side view taken through one of the retorts of an underfeed stoker showing one of the adjustable ram box extension plates.

Fig. 2 is a view taken substantially along line 2 2 of Fig. 1.

Fig. 3 is a sectional view taken substantially along line 3--3 -of Fig. 1, and

Fig. 4 is a plan view of one of the adjustable ram box extension plates.

Referring to the drawings, the numeral 1 designates generally a conventional stoker of the multiple retort underfeed type comprising alternately disposed retorts 2, and tuyre rows 3. `The side walls 4 of the retorts 2 are secured at the upper ends thereof to brackets 5 provided in a front wall 6. Fuel from a hopper 7 is fed to the retorts 2 by a series of reciprocating rams 8 operating in cylinders 9 secured to the front wall 6.

The brackets 5 are substantially rectangular in cross section, as shown in Fig. 3, and are in substantial alignment with the tuyre rows 3. Bridging the space between adjacent brackets 5 are a series of air boxes 10 and 1l. Airrbox 10 is provided with flanged depending legs 12 and 13 which are bolted respectively to the upper surfaces of the associated brackets. Air box 11 is likewise provided with flanged legs 14 and 15 which are also bolted respectively, to the upper surfaces of the associated brackets 5. Ihe up-v per surfaces of brackets 5, and air boxes 10 and 11, are substantially flat, as shown in Figs. l and 3, and form supports for' the masonry 16. Air.

boxesl and 1I :are substantially triangularv in cross section, as shownin'fFig.- 1,' and the bottom walls 1'7 `and 18 respectively thereof are in substantial alignment and incline upwardly from front to rearof the wall 6.y The ybottom -Wall 18 of air box 11fterminates at the forward end ,there` of in a dependingportion 19 having a slightly inclined surface 20 which extendsV tothe mouth of cylinder 9.A` Dependingv p`ortion`19 is provided with an! open cylindrical? recess V121i 'which' receives the 4corre'spc'indingly'nshaped forward end portion 22 of a rain box extension plate 23. End portion 22 lis'provided with a radial s1ot'24 which engages a rod` vextending longitudinally-'of recess 21, and which is `suitably secured at the ends thereof v't-o the legs 14 an`d`15" of air box' 11; Plate A23 is substantially rectangular in-shape (Fig. 4) ,-ito'ccupy'- ing substantiallythe `entire space between v adjay cent brackets 5,v andthe freey 'end-'401 thereof ex#- tending substantially to the innersurface of' wall 6. Plate 23 issec'ured in adjusted position by bolts 26 and 2'7, which extend; Lthrough internally threaded openingsf'provided in ears 28- a'nd'29-exf tending from theupper surface of plate v23rnearY the free end thereof. To adjust plate 23 to any of its positions of adjustment it is only necessary to loosen the bolts 26 and 27 and swing the same about rod 25 to the new position and then tighten bolts 26 and 27. The ends of bolts 26 and 27 frictionally engage the inner surfaces of legs 12 and 13 of air box 10, or the side Walls of brackets 5 y depending upon the position to which the plate is adjusted. Apertures may be provided in the side walls of brackets 5 and in legs 12, and 15 for receiving these bolts if a more positive securing means is desired. In the present instance apair of blocks 30 and 31 are provided between plate 23 and air box 10 to further secure the plate against upward movement during operation of the stoker. A series' of reinforcing ribs 32 are also provided on the upper surface of plate 23 as shown in Fig. 4, the lower surface of plate 23 the inclined surface 20 of depending portion 19,

thereby presenting a smooth continuous surface to the fuel fed by the rams 8. n

An'upper coal plate 33 extends from the mouth of cylinder 9 and rests upon a dead plate 34. provided in the bottom of the retort 2, forming the sary to swing plate 23 upwardly the desiredl UNITED STATES PATENT OFFICE `being smooth and in substantial alignment withV y amount and secure the same in position. On the other hand, if it is desired to decrease the depth of the fuel bed, or to pack the fuel more tightly, plate 23 is lowered. By this construction it is possible to regulate the fuel bed so as to obtain the best efficiencies in operation, and also to enable the furnace to efficiently burn different kinds of fuel. l

While the device herein described is admirably adapted to fulll'the objects primarily stated, it is to be understood that it is not intended to confine the invention to the one embodiment herein shown since it may be embodied in other forms, all coming within the scope of theclaims which follow. y

What is claimed is: Y

k1. In an underfeed stoker,the combination of a retort, a fuel feeding ram for s'aidretort, of a wall disposed between said ram and said retort having a passage therein through which the fuel fedI by said ram passes to said retort, 'anadjustable ram box extension plate comprising aportion of theupper wall of said passage for regulating the depth and density of the fuel in said retort, means for pivotallysupporting one end ofsaid plate and means provided near vthe other. end of saidy plate for retaining the same in different positions of adjustment.

2. In an underfeed-stoker, the combination of alternately disposed retorts and tuyre'rows, of a fuel feeding ramforj each retort, a wall vdisposed between-said retorts `andrams having passages therein through which the fuel fed by Vsaid rams passes to said retorts, an adjustable ram box extension plate for f each passage, said platesv forming a` portion-of the upper walls of said passages, means forpivotally supporting one end of said platesand means provided near the kother end of said platesforretaining lthesame in different positions of adjustment.l

3, In an'underfeedstoker, the combination of a retort, a fuel feeding ram for said retort, of a wall disposed between saidram and said retort having an opening through which the fuel'fed by said ram passes to said retort, adjustable means provided in the upper wall of said passage for varying the depth and density of the fuel in said retort, said means comprising a plate, a cylindrical recess for receiving one end of said plate, interlocking means provided on said plate and in said recess to prevent longitudinal movement of said plate, and means provided in the other end of said plate for retaining the same in various positions of adjustment.

Y4. In an underfeed Stoker, the combination of a retort, a fuel feeding ram for said retort, of a wall disposed between said ram and retort, having an opening therein through which the fuel from "said ram passes to said retort, an adjustable ram box extension plate comprising the upper wall of said passage, a cylindrical recess for receiving one endof said plate, a rod extending through l; said recess, a slot providedin said plate adapted to engage said rod and. adapted upon a predeterminedv movement of said plate to hold the latter against -longitudinal movement while permitting said plate to swing about said rod as a pivot, and means for securing the plate in various positions of adjustment.

. 5. Af` ram box extensiony plate, comprising a substantially rectangular rbody portion, substantiallycylindrical means provided at one end of said plate, means provided in said cylindrical lmeans adapting said plate for pivotal movement,

and locking means provided on said plate for holding the same in adjusted position.

6. An adjustable ram box extension plate, comprising a substantially rectangular body portion,

substantially cylindrical means provided at one end of said plate, a slot provided in said cylindrical means adapted to receive interlocking means for pivotally mounting said plate, projections provided on the side edges of said plate adapted to receive locking bolts to retain said plate in adjusted position, and reinforcing ribs provided on said plate.

HERBERT E. PRESTON. 

